user interfaces we have created which run on the server from the same codebase and database (e.g. Cycling Sorted);

proxied sites which we host, running under different domain names.

Downtime, monitoring and switchover

Our main and development servers are monitored via a ping service and 5-minutely custom API monitoring, both resulting in SMS messages to the sysops/developers if no response or an invalid is receiving.

We aim to exceed 99% uptime.

Historical downtime since December 2008 has been well in excess of this:

no periods of extended downtime;

two several-hour period of downtime due to upstream network connectivity issues;